The National Oil Hub Cap Plug is the perfect solution for protecting your wheel hub from corrosive elements and contaminants. This unique slit-style vent plug is designed to fit securely and provide a tight seal, keeping out dirt, dust and other debris. The nitrile construction is durable and resistant to oil, grease and other chemicals, making it ideal for use in a variety of automotive and industrial applications. FleetPride is your First Click in Heavy Duty®.